/* 头部容器 */
.site-header {
    padding-block: .687rem;
    background: #1f2937;
    padding-left: 0.5rem;
    padding-right: 0.5rem;


}

/* 头部内部布局容器 */
.site-header .container {
    max-width: none;
    width: 100%;
    margin-inline: 0;
    padding: 0 clamp(8px, 2vw, 24px);
}

/* Logo 区域 */
.logo-wrap {
    display: flex;
    align-items: center;
    gap: .5rem;
    text-decoration: none;
}

.logo-text {
    font-size: 1.5rem;
    font-weight: 600;
    color: #fff;
}

/* 导航菜单 */
.nav-list {
    list-style: none;
    display: flex;
    gap: 1.75rem;
    margin: 0;
    padding: 0;
}

.nav-list a {
    color: #fff;
    font-weight: 500;
    text-decoration: none;
    position: relative;
    transition: color .2s;
}

/* hover/focus 变色 */
.nav-list a:hover,
.nav-list a:focus-visible {
    color: var(--brand);
}

/* 下划线伪元素 */
.nav-list a::after {
    content: "";
    position: absolute;
    left: 0;
    bottom: -4px;
    width: 0;
    height: 2px;
    background: var(--brand);
    transition: width .25s;
}

/* 展开下划线：hover/focus + 当前激活项 */
.nav-list a.active::after,
.nav-list a:hover::after,
.nav-list a:focus-visible::after {
    width: 100%;
}

/* 可选：激活项文字变色 */
.nav-list a.active {
    color: var(--brand);
}

/* 图标按钮（如果有） */
.icon-btn {
    width: 24px;
    height: 24px;
    border: none;
    background: center/cover no-repeat;
    filter: invert(1);
    cursor: pointer;
}
